Last year, Alan Masarek made news as he left Google to become Vonage’s new CEO.
An Address Book stores the names and phone numbers of business and personal contacts on your phone, in the control panel or within a company directory.
Speed Dial or click to call the name or phone number of the contact. Some providers call this a "Dial by Name Directory."
In addition to the features above (control panel, speed dial, click to call), the address book works with Office - Outlook Integration. You can store email addresses in addition to phone numbers in your address book.